1. Field of the Invention
The invention relates generally to a flat panel display technology and more particularly, to a gate driver having a resistance compensation function and a liquid crystal display using the gate driver.
2. Description of Related Art
In recent years, with great advance in the semiconductor technique, portable electronic devices and flat panel displays (FPDs) have been rapidly developed. Among the various types of flat panel displays, liquid crystal displays (LCDs) have become the mainstream among the display products mainly due to their advantages such as low operating voltage, lack of harmful radiation, light weight, and small footprint.
Generally speaking, as shown in FIG. 1, when a conventional gate driver 103 is employed in a high resolution display panel 101, since a wiring distance from each of the output channels OUT of the gate driver 103 to the display panel 101 is different (e.g., a wiring distance to the region A of the display panel 101 is shorter than a wiring distance to the regions B and C), a layout resistance variation between each of the output channels OUT of the gate driver 103 and the display panel 101 is overly large. For example, a smallest layout resistance is approximately 82Ω, whereas a largest layout resistance is approximately 1021Ω.
Accordingly, based on each of the output channels OUT of the gate driver 103 having a same loading on the display panel 101, and since the layout resistance variation between each of the output channels OUT of the gate driver 103 and the display panel 101 is overly large (e.g., may be a difference of several hundred ohms), therefore a scan signal outputted by each of the output channels OUT of the gate driver 103 may have too large a disparity.
Consequently, in condition of the display panel 101 is a normally black type, when the gate driver 103 outputs scan signals having large variations through all of its output channels OUT to the display panel to turn on all the scan lines (e.g., all the pixels), the display panel 101 does not display an ideal all black image. Rather, a so-called “multi-band phenomenon” may be generated (e.g., the middle region A of the display panel 101 may display the black image, while the regions B and C of the display panel 101 may display a continuous gradient gray image), thereby affecting the quality of images displayed by the display panel 101.